A woman walks down High Street on her lunch hour. Passing a bus kiosk, she waves her Samsung Galaxy at a “smart poster” to download coupons. Minutes later she enters a favorite eatery, orders lunch, and flashes her phone at a point-of-sale device to “cash in” a discount on her entree. On the bus ride back to the office, she uses her smart phone to pay the fare.

Welcome to the center of the mobile wallet universe — not New York, London or Tokyo, but Seoul, South Korea — where up to three million customers use their smart phones for “contactless payment.” Provided by KT and SK Telecom, Korea’s mobile wallet services are the vanguard of one of the hottest trends in mobility: “near field communications” (NFC), a communications standard widely viewed as the platform that will transform smart phones into mobile wallets.